Did you have an alternate launcher installed? I've seen reports where next launcher is not compatible with 4.4, and the nex7 hangs on boot. If this is the case, boot into safe mode and change to stock launcher.

Safe mode: hold volume down when you see the Google logo until boot finishes.

yes rooted, reg. ota, "nexus 7 -18001A", nova launcher installed. cannot boot passed "no command screen. I have removed back and unpluged and repluged Batt. still as far as can boot is to no command screen. cannot turn it off, it keeps comming back on. I also tried the reset button.I appreciate everyones help.

I finely get a menu on my nexus 7-2012 that give me these options which still don't boot the device. "start, power off, recovery mode, restart bootloader" the only one that works in "power off" thats all I can get on the screen except the red triangle.